Jurnal Ilmu dan Teknologi Kelautan Tropis

Types and Composition of Marine Debris in Randusanga Coastal, Brebes, Central Java

Ferlynda El Haq — 2024-10-27

The problem of plastic waste in Indonesia is considered an emergency status, following research results that place Indonesia as the largest contributor to marine plastic waste in the world after China. The lack of information about marine pollution on the coast is a problem in its handling, especially in Brebes Regency, Central Java. This study aims to identify the types of marine debris and estimate their composition and distribution on the coast of Randusanga Brebes Beach. Marine debris sampling was carried out using the quadrant transect observation method which was carried out three times with a total of 15 transects in August-October 2021. Data was analyzed using Graphical Data Analysis (GDA) approach. Of the various types of waste found, plastic waste was the most dominant waste found with 869 items, followed by 190 items of plastic foam, 57 items of paper and cardboard, 48 items of wood, 36 items of rubber, 34 items of other materials, 22 items of metal, 8 items of cloth, as well as glass or ceramic as much as 4 grains. Based on size, macro-sized waste is the most commonly found waste. The total amount of macro debris found at the study site was 1,222 items, while the meso debris was 66 items. Percentage composition of tents: plastic bags (71%), plastic foam (15%), fabrics (4%), glass and ceramics (0%), metal (0%), paper and cardboard (4%), rubber (0%) , wood (2%), other materials (4%). Types of plastic waste based on the Resin Indetification Code (RIC) consist of polypropylane (PP), low density polyethylene (LDPE), others (OT), polystyrene (PS), high density polyethylene (HDPE), polyethylene terephthalate (PET/PETE) waste. The high abundance of marine debris every month is closely related to the lack of public awareness of the sustainability of the surrounding ecosystem and the lack of awareness of the implementation of Government Regulations regarding the handling of applicable waste.

COMPARISON OF ARIMA AND LSTM METHODS IN PREDICTING JAKARTA SEA LEVEL

Yanuar Nurul Hilal — 2024-10-27

As a coastal city, Jakarta faces enormous risks from sea level rise brought on by climate change, and it is critical to create efficient plans to anticipate and minimize any potential negative effects. Predictive modeling is essential in addressing this challenge in order to anticipate and mitigate any potential negative effects of sea level rise. Therefore, research was conducted with the aim of comparing the performance of two prediction methods, namely Autoregressive Integrated Moving Average (ARIMA) and Long Short-Term Memory (LSTM). Sea level was predicted using both techniques up to the end of 2023. Performance indicators, including Mean Absolute Error (MAE), Mean Absolute Percentage Error (MAPE), and Root Mean Square Error (RMSE), were employed to assess the quality of both prediction models. The result shows that the ARIMA (1,1,4) model is more effective in predicting sea level than the LSTM. The MAE, MAPE, and RMSE values for ARIMA (1,1,4) are 7.19, 4.86%, and 10.35, respectively. In the meantime, the sea level in Jakarta is predicted to remain reasonably steady, according to the forecasted findings from both models. This study is expected to make a significant contribution to understanding and mitigating the potential impacts of sea level rise in Jakarta as a result of climate change.

MORPHOLOGICAL VARIATIONS IN MUD CLAM Polymesoda erosa (Lightfoot) USING FLUCTUATING ASYMMETRY ANALYSIS IN LA UNION, CABADBARAN CITY, AGUSAN DEL NORTE, PHILIPPINES

Noel Sastrillas — 2024-10-27

A geometric morphometric study was conducted on the population of Polymesoda erosa in La Union, Cabadbaran City, to investigate the morphological variations using fluctuating asymmetry (FA) analysis. FA acts as a reliable indicator of ecological stress and developmental instability since it detects genetic or environmental changes that an organism experiences. A total of ninety (90) individual mud clams were randomly collected and analyze. Water and soil samples were also collected to gather data on the degree of body variations and the impact of external factors on P. erosa. The result of the analysis using the SAGE software revealed a highly significant fluctuating asymmetry (P 0.0001). Significant variations in individuals, sides, and the interaction between individuals and sides symmetry were mostly responsible for the substantial variances seen in mud clam species. Particularly, landmarks 10 (dorsal margin maxima) and 13 (anterior margin maxima) exhibited notable variations. For the water quality results, the mud clam's internal valve was likely to be relatively unaffected or minimally impacted, but the level of nickel was high. In conclusion, the fluctuating asymmetry of P. erosa can be attributed to a stressed environment. Unfavorable environmental factors cause an organism's morphology to change, affecting its symmetry.

MORPHOLOGICAL AND MOLECULAR COMPARISON OF AREOLATE GROUPER (Epinephelus areolatus) FROM SAUDI ARABIA AND INDONESIA

Muhammad Browijoyo Santanumurti — 2024-10-27

Grouper (subfamily Epinephelinae) is one of the largest groups of fish in the oceans. Identification of groupers, especially the Epinephelus, is conducted based on morphological characteristics (color, pattern, body shape, and size. However, the identification process is difficult to differentiate morphologically because of their similar characteristics. One method that can be applied is DNA barcoding. This study aimed to compare groupers from Saudi Arabia and Indonesia. Morphological and molecular identification results show that the grouper from this study (from Yanbu, Saudi Arabia, and Lamongan, Indonesia) was Epinephelus areolatus (areolate grouper). Morphologically, grouper samples from Yanbu (Saudi Arabia) were as follows: dorsal fin X-XI/12-15; anal fins II-III/8-9; pectoral fins 13-15; pelvic fin I-5; lateral line scales 48-53; vertebrae 24. Meanwhile, the meristic results of groupers from Lamongan (Indonesia) were as follows: dorsal fins X-XI/15-17; anal fins II-III/8; pectoral fins 16-19; pelvic fin I-5; lateral line scales 48-53; vertebrae 24. The morphological differences between E. areolatus from Saudi Arabia and Indonesia were its spots and caudal fin. Molecular results on E. areolatus showed different clades. Samples from Saudi Arabia belonged to the Western Indian Ocean clade while Indonesia belonged to the Western Pacific. This showed that there were morphological and molecular differences between E. areolatus from Yanbu (Saudi Arabia) and Lamongan (Indonesia). The COI gene sequences of areolate grouper were submitted to NCBI (accession number PP388919.1 for Lamongan and PP388920.1 for Saudi Arabia). This research data can be used as a reference for conservation.

Preliminary Study on Habitat Characteristics of Endemic Banggai Cardinal Fish Marine Ornamental Fish (Pterapogon kauderni) in Baubau City Waters

Cahyani Waode Sitti — 2024-10-27

The Banggai dragonfly or better known as the Banggai Cardinal Fish (BCF) is an endemic fish originating from the waters of the Banggai Islands, Central Sulawesi. However, its distribution has been found, among others, in Bali waters, Ambon Bay, Kendari waters, Strait Lembeh and the Baubau City waters. The high demand from seawater ornamental fish collectors makes this species have high economic value, so this species is vulnerable to exploitation. This research was conducted due to the lack of information regarding the endemic species of BCF found in the Baubau City waters. Fish abundance data was collected using a visual census, that is the Line Intercept Transect (LIT) method. The length of the transect used is 50 meters with a coverage area of 2.5 meters to the left and 2.5 meters to the right. Water quality parameters were also taken to determine the suitability of the Banggai Cardinal Fish habitat in the Baubau City waters. The purpose of this study was to study the abundance and microhabitat of the BCF as preliminary information on the existence of this fish in Baubau City. The results of observations at 4 stations found a total population of 637 individuals/m², which inhabits different microhabitat at each stasiun include: sea urchins, coral reefs, seagrasses and seaweed (Sargassum sp.). The introduced Banggai Cardinal Fish are able to adapt to new aquatic environments. The existence of this fish, especially in the waters of Baubau City, is expected to provide ecosystem services while still paying attention to its ecological function.

The Benefits of Managing The Terubuk Fish Sanctuary (SPT) for Coastal Communities in Bengkalis Waters, Riau: a Social-Ecological Systems Approach

Muhammad Nur Arkham — 2024-10-27

The establishment of the Terubuk Fish Sanctuary (SPT) under Bengkalis Regent Regulation No. 15 of 2010 and the Minister of Marine Affairs and Fisheries Decree No. KEP.59/MEN/2011 has undoubtedly had positive social and ecological impacts. This study aims to assess the social and ecological benefits of the SPT for coastal communities in Bengkalis Waters, Riau. Data were collected through interviews and fishery production analysis based on available data from 2008 to 2016. The presence of Terubuk fish in the waters of Bengkalis, Meranti Islands, and Siak is closely linked to historical and cultural significance. A 10-year production forecast model indicated a decline in Terubuk production, with a predicted decrease of 1.37 tons per year (-0.58%) based on the S-Curve model. Statistical analysis (t-test) also showed no significant difference in Terubuk production before and after the issuance of the regulation (P-Value > 0.005). Overall, Terubuk fishery management in the Riau Province waters has not been effective with only the issuance of area management regulations. Strategic steps are needed, including increasing community involvement in management, enhancing supervision, and enforcing laws to better conserve the Terubuk fishery.

Species Composition and Density of Sponges (Porifera: Demospongiae) on Panggang Island, Kepulauan Seribu, DKI Jakarta

Wahyu Adi Setyaningsih — 2024-10-27

Sponges are symbiotic organisms that play a significant role in coastal ecosystems, such as filtering water, decomposing organic material into nutrients, providing shelter for microorganisms, and contributing to sediment stability and binding. This study aims to identify the composition and species diversity of sponges found in seagrass habitats on Panggang Island, Thousand Islands, DKI Jakarta. The research was conducted at three locations using a 50-meter line transect and 11 square transects measuring 0.5 x 0.5 meters along each line. Sponge samples were collected by cutting small pieces from each sponge for spicule analysis. The results indicate that a total of 10 sponge species were recorded across all research locations, dominated by Chondrilla caribensis forma, with sponge density values ranging from 0 to 13 individuals/m². The sponge diversity index on Panggang Island falls within the moderate category, indicating that the distribution of genera within the sponge community is relatively even. Phosphate concentration and current velocity showed a strong positive correlation with sponge density, while temperature exhibited a positive correlation with seagrass density. Conversely, the correlation between sponge density and seagrass density was relatively weak, supporting the findings that these two components do not have a close relationship within the observed ecosystem.

Comparative Analysis of Seawater Quality of Youtefa and Yos Sudarso Bay, Jayapura, Papua

Muhammad Hisyam — 2024-10-27

Youtefa Bay and Yos Sudarso Bay are bays located in Jayapura City. Yotefa Bay is a semi-closed coastal area because it is a small bay located in Yos Sudarso Bay. This condition makes the two bays have quite striking differences in sea dynamics. This is reinforced by the geographical location of the waters of Jayapura City which directly faces the Pacific Ocean which greatly affects the condition of the waters and the richness of its ecosystem. The richness of the coastal ecosystem in Youtefa Bay and Yos Sudarso Bay is closely related to the lives of the people living around the two bays. This study aims to analyze the comparison of seawater quality parameters in Youtefa Bay and Yos Sudarso Bay. The seawater quality data in question are temperature, salinity, and dissolved oxygen (DO) data. The study was conducted by taking temperature, salinity, and DO data in both bays at depths of 0 meters, 3 meters, and 5 meters. From these data, a comparative analysis will be carried out between sampling points to see the differences in values. In addition, an analysis of the average parameter differences between the two bays was also carried out. Based on the research results, each parameter has a fairly uniform distribution between each sampling point in each bay. The average temperature and DO values in Youtefa Bay are higher than Yos Sudarso Bay because Yotefa Bay is a semi-enclosed water with many seagrass ecosystems in the bay. In addition, the average salinity value of Yos Sudarso Bay is higher than Youtefa Bay because Youtefa Bay receives direct input from the Pacific Ocean. Thus, based on the analysis, the temperature and salinity of the two bays show significant differences compared to the DO values in the two bays.

The Antibacterial Activity of Methanol Extract of Xylovcarpus Granatum Fruit Seeds Against Tilapia (Oreochromis niloticus) Bacterial Isolates

Andi Noor Asikin — 2024-10-27

The use of various types of mangroves is effectively used as a natural ingredient in inhibiting the growth of bacteria in fish. Fruit of Xylocarpus granatum contains secondary metabolites that have the potential as natural antibacterials. This study aims to determine the antibacterial activity and determine the value of the Minimum inhibitory concentration (MIC) of the methanol extract of X. granatum fruit seeds. The research stages consisted of seed preparation and extraction of X. granatum, isolation of bacteria from tilapia gills, inhibition testing, MIC testing, and Total Plate Count (TPC) testing. Preparation was done by thinly slicing the seeds of X. granatum and air-wdrying for 30 days. The dried seeds (simplicia) were reduced in size using a blender and then extracted by maceration using 98% methanol solvent for 24 hours, then filtered. The filtrate was separated from the methanol solvent using a rotary evaporator at a temperature of 600 °C to obtain the extract of X. granatum seeds. The content of secondary metabolites of the methanol extract of X. granatum seeds was found to be alkaloids, triterpenoids, flavonoids, saponins, phenols, and tannins. The treatment in this study were used methanol extract of X. granatum seeds with 3 concentrations (100 ppm, 500 ppm, 1000 ppm) and positive control (Chloramphenicol) 1000 ppm and negative control (sterile distilled water). The parameters observed were the inhibitory activity, the MIC, and the TPC. The results showed that the methanol extract of X. granatum fruit seeds had the ability to inhibit the growth of bacteria isolated from the gills of tilapia fish with moderate categories (9-9.8 mm) at concentrations of 100 ppm and 500 ppm and the concentrations of 1000 ppm with strong categories (11.5 mm) at 48 hours. The MIC of X. granatum seed methanolic extract on isolates of tilapia gill bacteria was at a concentration of 40 ppm. The results of the TPC test at a concentration of 40 ppm were 5.5×10⁷CFU/ml, with inhibition activity against 91.67% of bacterial growth.